[Joel5000]

Going through the hops in the freezer to get ready for my brew day tomorrow, and I'm realizing that I have hops going all the way back to 2013 harvest (fortunately they are all labelled with the harvest year).  I know the 2016 are still fine, but I'm wondering if the older ones should go.  They are all vacuum sealed and have been kept frozen.  Hate to throw them away if they are still usable.

[KellerBrauer]

Greetings Joel - my suggestion is to go ahead and use them.  If they have been shielded from both light and air while kept frozen, the odds are they’re still usable.  Will they carry their full potential as fresh hops?  I doubt it.  But using them in an IPA, for example, along with other fresh hops certainly can’t hurt.

[dmtaylor]

If they smell good, they're good.  If they smell freezer-burned, they're not.  If in between, they're in between and thus should be reserved for bittering only.

[Horseflesh]

I keep a lot of spices in the freezer... some in vacuum bags, some just in heavy-duty ziplocks. I've had them for years and they are all still great. I bet your vac-sealed hops are probably fine too.

[jtoots]

Anything that is deemed "too old", if it hasn't gone bad, could potentially be saved for future use as aged hops in sour applications.

[yso191]

I would say that it depends on what you want to use them for.  If for flavor and aroma (oils), go with your nose.  If for alpha acids... I wouldn't without finding out what the HSI is and doing the calculation to see what is still there in terms of bittering ability.